While the trend to use more and more design intellectual property (IP) has considerably reduced design effort per gate, it has had the exact inverse effect on the functional verification effort. In fact, since integrating multiple design IP blocks is now the norm, verification has become the dominant task and source of risk in system-on-chip (SOC) projects. To cope with this challenge and contain these risks, design and verification teams recognize they need help.

The majority of design and verification teams today use verification IP (VIP) in one form or another. In fact, VIP is essential for any complex protocol or bus standard. Teams achieving the greatest success combine VIP use with a verification reuse strategy and a methodology that begins with an initial plan and goes all the way through to full verification closure.

Further contributing to verification IP's ascendance is the need to ensure compliance with the complex protocol's checklists. This is a major undertaking in itself and also must span the full verification process. VIP's end goal is to improve the verification process while reducing your verification project's risk profile. However, the decision as to which VIP to use has only gotten more complicated. Just as automobiles range from stripped down to high end models, several VIP classes now exist.

Since VIP is not created equal, it is critical to select not just any VIP, but the right VIP that balances your needs and resources against risks. When the wrong VIP is selected teams commonly face project delays and even outright project cancellations. This article will help you optimize VIP selection decisions. Furthermore, it will familiarize you with the various classes of VIP and the key issues to consider in your VIP selection.

Key considerations in VIP selection
 

Since different classes of VIP vary significantly, in functionality it is essential to know what capabilities you need. Start the selection process by identifying the critical requirements for the verification project. Listed below are the most common questions to consider.

• Will this verification effort be a "quick-and-dirty" integration where you trust the blocks, or will you perform a complete functionality verification?
• How will you reuse VIP when moving from block to chip or to system level verification?
• How will you ensure compliance for any complex protocols?
• Will you simultaneously verify multiple protocols?
• How will you specify your verification goals and measure verification progress?

How you answer these questions narrows the range of applicable VIP. For example, "quick-and-dirty" integration requires far less capable VIP than a complete verification. Simple integration can be done with a Bus Functional Model (BFM). Somewhat more complex projects can succeed with "Testbench VIP."

On the other hand, IP development and SOC projects place far greater stress on the VIP. They need End-to-End VIP that provides a plan and clear metrics for measuring completeness and a compliance solution and that spans the full verification process from architectural modeling to block design and on to full chip/system verification. It also must span the full set of verification engines including formal analysis, simulation, acceleration and emulation.

It is also important to consider your future needs. Even if you don't need many of these capabilities now, it often makes sense to select VIP with headroom to retain your investment as your needs grow.

Matching your needs relative to VIP capabilities
 

There are three primary classes of VIP. They are BFMs, "Testbench VIP," and "End-to-End VIP." Each class of VIP has its own features and tradeoffs. They are characterized in Figure 1 below.

BFMs and Testbench VIP will serve the need for basic block connectivity checkout. For anything more complex, End-to-End VIP is needed. While a variety of suppliers offer commercial VIP, you'll find that most semiconductor and systems companies internally develop only BFMs.

Page 2: Verification IP takes a broader role
Page 3: Verification IP takes a broader role